Part of it is certainly a lack of catechesis. VCII sure threw out a lot of babies with the bathwater.
Of course it's not a new thing. There's a saying variously attributed (to St. John Chrysostom, St. John Eudes, and St. Athanasius) that "the floor of Hell is paved with the skulls of bishops."
VII is certainly to blame (Or more specifically, our American Bishops using the Council as a reason to do what they did).
As an older GenXer, I believe that we were the first to grow up with and suffer from the effects. My BF is 2 years older, but came form a very orthodox area (they had the TLM uninterrupted until about 4 years ago). He knows so much more of the actual practices if the Church, although there is a lot he doesn't know of beliefs and theology. I can't blame that on VII.